I think this is it exactly - and also why I never understood the idea that they would substantially use virtual queues. The queues absorb a lot of crowds. Without people in the queues, the park would still seem crowded in most other areas. At, say, 25% capacity, if few people are in line for rides, you might have 15-20k people wondering about the hub and Main Street and other common areas. While it's certainly worrisome that people won't abide by distancing in the queues (and even more worrisome, use that time out of sight of more of the CMs to not follow mask rules), for better or worse, Disney seems to be trusting people to follow the distancing markers in the queues so as not to have a lot of crowds throughout the park where it's harder for people to follow distancing because everyone's just milling about and going different ways. Think about Main Street and the Hub with crowds, it's a bit chaotic.